Try really had not to speculate. Most of the time you will be wrong (as most of us LBS were when we speculated) and it will just drive you nuts.
I am sure she was sad and stressed while you were deployed and I can't pretend to know what that might feel like. BUT what did she do to take control of her feelings while you were deployed that was healthy and positive? It doesn't sound like much.
I read your post as if YOU should take accountability for being deployed for your job! Now if you treated her poorly while you were deployed, well, you will need to own that but you can't own "her" deployment issues that she had the power to work on.
